Declining memory in the aged is a major social and economic problem. The goals of the proposed research are (1) to establish an animal model of declining memory in the aged; (2) to develop techniques for accelerating or accentuating aging of those structures in the central nervous system responsible for declining memory in the aged; (3) to study the effects of prior environmental and physiological events on declining memory in aged rats and (4) to search for and evaluate pharmacological and physiological procedures for ameliorating declining memory in the aged.